Washington Post Assistant Managing Editor Bob Woodward testified under oath Monday in the CIA leak case that a senior administration official told him about CIA operative Valerie Plame and her position at the agency nearly a month before her identity was disclosed.

In a more than two-hour deposition, Woodward told Special Counsel Patrick J. Fitzgerald that the official casually told him in mid-June 2003 that Plame worked as a CIA analyst on weapons of mass destruction, and that he did not believe the information to be classified or sensitive, according to a statement Woodward released yesterday.

Fitzgerald interviewed Woodward about the previously undisclosed conversation after the official alerted the prosecutor to it on Nov. 3 -- one week after Vice President Cheney's chief of staff, I. Lewis "Scooter" Libby, was indicted in the investigation.

Citing a confidentiality agreement in which the source freed Woodward to testify but would not allow him to discuss their conversations publicly, Woodward and Post editors refused to disclose the official's name or provide crucial details about the testimony. Woodward did not share the information with Washington Post Executive Editor Leonard Downie Jr. until last month, and the only Post reporter whom Woodward said he remembers telling in the summer of 2003 does not recall the conversation taking place.

Woodward said he also testified that he met with Libby on June 27, 2003, and discussed Iraq policy as part of his research for a book on President Bush's march to war. He said he does not believe Libby said anything about Plame.

He also told Fitzgerald that it is possible he asked Libby about Plame or her husband, former ambassador Joseph C. Wilson IV. He based that testimony on an 18-page list of questions he planned to ask Libby in an interview that included the phrases "yellowcake" and "Joe Wilson's wife." Woodward said in his statement, however, that "I had no recollection" of mentioning the pair to Libby. He also said that his original government source did not mention Plame by name, referring to her only as "Wilson's wife."

Woodward's testimony appears to change key elements in the chronology Fitzgerald laid out in his investigation and announced when indicting Libby three weeks ago. It would make the unnamed official -- not Libby -- the first government employee to disclose Plame's CIA employment to a reporter. It would also make Woodward, who has been publicly critical of the investigation, the first reporter known to have learned about Plame from a government source.

The testimony, however, does not appear to shed new light on whether Libby is guilty of lying and obstructing justice in the nearly two-year-old probe or provide new insight into the role of senior Bush adviser Karl Rove, who remains under investigation.

Mark Corallo, a spokesman for Rove, said that Rove is not the unnamed official who told Woodward about Plame and that he did not discuss Plame with Woodward.

William Jeffress Jr., one of Libby's lawyers, said yesterday that Woodward's testimony undermines Fitzgerald's public claims about his client and raises questions about what else the prosecutor may not know. Libby has said he learned Plame's identity from NBC's Tim Russert.

"If what Woodward says is so, will Mr. Fitzgerald now say he was wrong to say on TV that Scooter Libby was the first official to give this information to a reporter?" Jeffress said last night. "The second question I would have is: Why did Mr. Fitzgerald indict Mr. Libby before fully investigating what other reporters knew about Wilson's wife?"

Fitzgerald has spent nearly two years investigating whether senior Bush administration officials illegally leaked classified information -- Plame's identity as a CIA operative -- to reporters to discredit allegations made by Wilson. Plame's name was revealed in a July 14, 2003, column by Robert D. Novak, eight days after Wilson publicly accused the administration of twisting intelligence to justify the Iraq war. Fitzgerald's spokesman, Randall Samborn, declined to comment yesterday.